Discrete-Time MPTCP Flow Control for Channels with Diverse Delays and Uncertain Capacity
Przemysław Ignaciuk, Michał Morawski · 2018
The TCP protocol provides the control framework for most of the today Internet traffic. Since its development over forty years ago, however, the end-points have not benefited from multiple interfaces installed for redundancy purposes in the underlying equipment. In the case of failure, the logical connection has been broken or stalled. In order to remedy this situation, a multipath version of TCP - MPTCP - has recently been elaborated. It allows for simultaneous use of a set of transmission paths and interfaces, yet requires appropriate means of coordination. This paper presents a discrete-time model of data exchange process subject to MPTCP master control and provides a new flow control algorithm for the paths with diverse parameters, e.g., different delays. The algorithm establishes a feasible (non-negative and bounded) input signal and finite data queue length despite uncertain networking conditions. The properties of the designed control system are analyzed formally and illustrated by numerical tests.